Cardiac pacemakers such as leadless cardiac pacemakers are used to sense and pace hearts that are susceptible to a variety of incorrect heart rhythms, including but not limited to bradycardia, which is a slow heart rate, and tachycardia, which is a high heart rate. In some cases, there may be a desire to remove a previously implanted leadless cardiac pacemaker. Since these devices are designed for long life, in many cases substantial tissue growth (e.g. endothelialization) around and even over the leadless cardiac pacemaker may occur, particularly with chronically (long-term) implanted devices. Tissue growth can complicate removal of the implanted device. Accordingly, there is a desire to provide implantable devices that are easier to extract, even when chronically implanted.